Method of making short metal articles



Dec. 2, 1958 1. s. LAWSON METHOD OF MAKING SHORT METAL ARTICLES Filed June 2, 1955 Unite States This invention relates to a method for continuously producing elements of predetermined comparatively short length from an endless metal ribbon. More particularly, the invention is directed to a process for continuously producing multiples of accurately measured indications on an endless metal ribbon, forming the ribbon into desired cross sectional shape, and successively breaking the formed stock at the measured indications into separate elements.

The objects and advantages of the invention reside par.- ticularly in the provision of a method for the continuous fabrication of accurately measured comparatively short lengths of formed material. The method enablesaccurate, uniform production of formed articles, rapid production of such articles, and economical production due to the fact that from the time the material, in. ribbon form, enters the device, there is no handling until each measured, formed article emerges from the other. end of the device.

Other advantages of the invention, such as itssimplicity of structure and arrangement of parts, will be more fully understood from a consideration of the following specifi? cation, taken in conjunction with'the accompanying drawing in which:

Figure 1 is a side elevational view of the invention showing the ribbon measuring structure and .brokenaway forming dies;

Figure 2 is a side elevational view of a break-offstructure in advance of the last set of forming dies;

Figure 3 is an enlarged fragmentary sectional view of the scoring and cutting die shown in Figure 1;

Figure 4 is a view similar to Figure 3, but showing another form of die;

Figure 5 is a fragmentary plan view of a portion of metal ribbon showing the partial cuts and projection formed by the device embodying the invention;

Figure 6 is a fragmentary sectional view, taken substantially on a line 6-6 of Figure 5; and

Figures 7 and 8 are views similar to FiguresS and 6 but showing another form of partial cut contemplated by the invention.

Formed strips are commonly used for many purposes such, for example, as trim or framing for doors and windows. Conventio-nally, the stock from which the strips are formed is of the nature of a spool or reel of metal ribbon. The ribbon is fed through the suitable forming dies to give it desired shape. As the shaped ribbon leaves these dies, it is measured into lengths and cut. A variety of means has heretofore been employed for measuring the length of the strips but these strips have generally been cut at the measured indications by some type of hand or power saw. When speed of production, coupled with accuracy, is required, it has not been found entirely satisfactory to measure and cut the material as it progresses from the forming dies. This has partly been due to the normally rather slow movement of a carriage by which to make the measured indications, the time taken for the saw to cut through the molded material and return of the carriage to the point of starting successive measurements;

2,862,292 Patented Dec. 2, 1958 Heretofore, it has been extremely difl icult to produce comparatively short formed articles due to the foregoing objections. However, by the present invention, it is proposed to increase the rapidity with which formed articles and therefore short elements may be made from metal ribbon stock. To accomplish this it is proposed to measure a length of material sufiicient for a multiplicity of elements and mark such elements by simultaneously scoring and partially cutting through the material when it is in ribbon form and prior to its passing through the forming dies. Such scoring and partial cutting, however, does not so weaken the strip as to in any way affect its movement through the forming dies and, thus, the material emerges from the forming dies as a continuous strip of desired cross sectional contour with the scored and cut points providing the only weakness. At the place of emergence of the molded material from the forming dies, it passes into a device that breaks olf successive articles. Such device takes the form of a stationary or movable abutment which serves to break the material apart at its points of weakness and a formed article of given length is produced.

Referring more particularly to the drawing, the reference numeral 10 is employed to generally designate a bed or stand on which the entire structure of the invention may be mounted. For purposes of description, the device may be considered .as consisting of three units; namely, a. measuring and scoring unit 11, forming dies 12, and severing unit 13.

The measuring and scoring unit 11 consists of two parts, 14 and. 16, which,.through their rigid connection by one or more rods 17 of. predetermined length, are adapted to move as one. along asuitable guide provided on the bed 10., Part of base 14 supports a lower die 19 which consists of a plane, upper surface 21' (Fig. 3) from which rises a center; projection 22. Anupper die 26 includes a depending portion 27 that is generally L-shaped in cross section. Centrally of the lowermost portion of the die is a depression which is adapted, to align with the projection 22 of the lower die when the dies meet. In the forward edge'28 of the lower portion is located a cutter 29, the edge thereof extending slightly below the. central depression above referred to Rearwardly of cutter 29 are a series of additional'cutters 29' preferably equally spaced to simultaneously produce a multiplicity of transverse scores or partial cuts. By such arrangement, it is intended that the ribbon be'simultaneously provided with a plurality of cross-scores 62, one score in each group being also a combined seore'and temporary projection or open ended blister 61 for a purpose hereinafter described. One end of the lower die 19 is connected by a spring 31 with an end plate 32' attached to the end of the unit 11. Any movement of the dies along the guide 18 in one direction sufficiently tensions the spring 31 so that, when the force, by which the dies are moved, is relieved, the springs will return them to the end of their travel on guide 18.

The part 16 includes a block 33 that is mounted'for slidable movement on a further guide or a continuation of guide 18. Secured in any suitable manner to the upper face of the block 33 is a further block 34. Theunder face of this block has a full length recess which combines with bl-ock33 to form a shallow lengthwise passageway 36. Projecting downwardly through a central slot in block 34 is a stop plate 37. This plate projects above block 34 and into the depending yoke 38 of a connector 39. A pin or other suitable means is employed to secure these parts together. The upper part of the connector is also formed with a yoke disposed at right angles to the depending yoke and this last mentioned yoke mounts a lever 41 by means of a pivot pin 42. The leverv 41 is not centered and thus includes a short arm 43 which terminates-in 2.. depending finger. 44 that overlies the ice block 34. The long arm 46 of the lever rests upon an incline of a block 47 that is permanently attached to the base of the unit 11. Block 47 is of the nature of a bridge and thus includes a horizontal passageway 48 therethrough. The incline of the block 47 faces the unit 11 and serves as a rest for the free end of arm 46, forming part of the lever 41. As already brought out, parts 14 and 16 are connected by one or more rods 17 which cause them to move as one along the guide 18. It will be understood that rods 17 may be removed and replaced by longer or shorter rods in order that the space between the parts 14 and 16 may be altered for operational purposes.

A trip 49 is mounted on the unit 11 and has operative connection with a switch 51. This switch is in the electrical circuit of a conventional press and, when closed, releases a ram 52 thereof for reciprocal movement. Presses of the type suitable for use with this invention are of conventional structure and frequently actuated by closing the switch of a circuit that controls the press clutch release. Thus, only a portion of the ram of such a press is disclosed, together with an operative switch.

The forming dies 12 are mounted in a frame 53 which supports suitable forming rolls 54. As is conventional in this structure, the rolls 54 may be adjusted toward or away from each other and may be removed entirely and replaced with other rolls by which to give different contour and cross-sectional shape to a continuous flat strip of metal ribbon that is passed through them. It is important to knOW that the path or direction for the ribbon, through the forming dies, is in the plane of the path of the ribbon through the measuring and indicating unit 11. The initial set or pair of rolls serves also to flatten the projection 61 in the strip which after serving as a point from which to measure the next succeeding group of scores has no further utility. This type of projection is readily returned to the plane of the metal ribbon by the rollers, and thus no material is removed or destroyed by its formation and subsequent flattening.

Attention is now directed to the severing or break-off unit 13 which is also mounted on the bed or stand 10. Adjacent the exit end of the forming dies 12 is a guide 56, shown as suitably mounted beyond the last pair of forming rolls to support the continuous formed strip. It will be understood, however, that in some instances it may be more desirable to locate suitable guide means just ahead of the last pair of rolls. In the present disclosure, the continuous strip is formed by the dies 12 into a tube which is permitted to pass freely to the abutment breakofi means 58. Abutment 58, which is preferably an angularly disposed block, is provided with a recessed inner surface to conform to the upper configuration of the molded article or stock. Block 58 is removable and replaceable to accommodate a formed strip other than of tubular form. The angularity of abutment 58 may also be varied to accommodate various shapes of formed strip by adjustment means such as bolt and nut assembly 59 which also secures block 58 to a slide 64 adjustable fore and aft on a support 63. Adjusting the slide 64 accommodates articles of different lengths.

To more fully understand the structure of the invention and the method of operation by which an endless metal ribbon may be measured, formed, and cut to measurement, the following brief description is presented. A conventional stand 82 mounts a reel of metal 83. This ribbon is hand fed into the measuring and indicating unit 11 between dies 19 and 26, and thence into the passageway 36. The stop plate 37 may interfere with passage of the ribbon but this is immaterial inasmuch as this hand operation is primarily to set the device up for subsequent automatic operation. The unit, as a whole, is now manually moved from one extreme end of travel at the right to its extreme position to the left, as viewed in the drawing. Die 19, during this movement, contacts trip 49, closing the switch 51 and actuating the ram 52. The

dies, being directly beneath the ram at this time, will be brought together, forming, in the ribbon, a transverse projection or blister. The blister, due to the design of this portion of the die, is partially cut from the ribbon and includes a raised edge that is in the direction of the ribbons travel. Simultaneously with forming the blister, the dies have produced a plurality of spaced full width transverse cuts in the ribbon. The depth of these cuts may be varied by adjustment of the die parts, but it will be understood that the ribbon is not severed nor rendered so weak that the subsequent forming operation would be jeopardized. The leading cut in the series is in line with the cut edge of the blister and thus it appears that the ribbon actually received a deep, transverse scoring with a small centered severance, followed by a series of plain transverse scores.

The ram, of course, has immediately returned to raised position and in doing so separates the dies. This unit, during travel, has expanded spring 31 which now functions to return the unit to its original position. Further hand feeding the ribbon brings the blister into contact with the block 37. As the ribbon is further moved, parts 14 and 16 move and, thus, arm 46 rides up the incline of block 47 and, with the finger 44 as a fulcrum, the lever now lifts plate 37 to a position above the blister. This movement serves two purposes; namely, to permit continued feeding of the ribbon through the block 34 and allow the spring 31 to return the unit to its original position. As the unit returns, lever 41 moves down the incline of the block 47 and allows the stop plate 37 to again rest on the upper surface of the ribbon where it will be in position to be contacted by the next blister.

The entry rollers 54 of the forming dies 12 are power driven and, when the end of the ribbon is fed into these dies, automatic operation of the structure commences and the ribbon will be continually unrolled, blistered, and partly severed, as already described, measured in accordance with the spacing of stop plate 37 and the cutter 29, and travel through the forming dies. Upon the entry of the ribbon into the dies, the first set of rollers flattens the blister. This is to enable accurate forming of the ribbon and also because the usefulness of the blister as a point of measurement is ended. As presently disclosed, the ribbon is to become a tube and so the rolls 54 are arranged in conventional manner for this purpose. The formed ribbon or tube now leaving the forming dies has been measured into lengths and such lengths 'indicated or designated by the scoring and partial cuts in the ribbon above described. Although these cuts are of insufficient depth to affect the ribbon as it passes through the dies, they are, nevertheless, sufficient to enable breaking the tube at the cut points by deflecting the leading end of the tube as it engages the abutment 58. As the tube continues to be fed into this unit, the end of guide 56 provides support for the tube as it moves to a position to be deflected. The tube is severed at the point previously scored or cut and the section thus severed quickly drops away from the unit, and is guided by chute 69 to a suitable receptacle (not shown). Shortly the new end of the tube will move off the guide 56 and into engagement with the break-off unit and the severing operation repeated when the weakened or partially cut place in the tube approaches the abutment. Although the abutment shown deflects the end of the formed tube downwardly, it will be understood that the abutment may be an upwardly or sidewardly inclined plane.

In some instances it may be desirable to produce articles having charnfered ends in which case the cutters may be formed, as shown at 129 and 129' in Figure 4 to produce V-shaped transverse cuts or scores as at 62.

Figures 5 and 6 are fragmentary plan and sectional views of the flat ribbon of metal scored at regular in tervals by the die structure of the scoring unit 11 with an open edged blister 61 combined with the leading cross score 62 of each group. The score or cut is in line with the cut edge of the blister and forms a transverse cut with a small central severance as shown.

When it is desirable to chamfer the ends of the articles being formed the transverse scores or notches will appear as shown in Figures 7 and 8 which are plan and sectional views of a ribbon of metal so scored. The open edge blister 61 may be incorporated with one of the group of cross scores as in the case of Figures 5 and 6.

From the foregoing it will be apparent that through the use of the above set out device, a sequence of operations are caused to take place which transform an endless metal ribbon into accurately measured molded sections of tubing. It will be clearly apparent that the methods and structures for measuring and indicating and severing lend themselves to very rapid operation, the speed of which being only limited by the rapidity with which the forming dies 12 can change the ribbon into desired cross sectional shape.

It will be understood that any obvious departure from the exact embodiment of the invention described above may be made without departing from the spirit and scope of the annexed claim.

What I claim is:

The method of forming short metal articles from continuous strip stock comprising the steps of simultaneously transversely grooving and producing an open edged temporary projection in the strip stock at spaced intervals equal to the combined length of a plurality of finished articles and transversely grooving the strip adjacent the first groove into connected blanks of predetermined length, determined by the desired length of the finished articles, measuring a succeeding length of strip stock from the projection for a repetition of the preceeding step, then passing the groove connected blanks through successive forming stages to form the same in desired cross-section and flatten the temporary projection, and breaking the blanks into individual finished articles solely by deflecting the formed stock transversely of the length thereof, subsequent to such forming stages.

References Cited in the file of this patent UNITED STATES PATENTS West Nov. 24, 

